Catheter tip with microelectrodes

Apparatus, comprising:

• a processor having a temperature module and an electropotential module;
• an insertion tube, configured to be inserted into a body cavity;
• a distal tip electrode having a cylindrical region defining a longitudinal axis connected to the insertion tube, the distal tip electrode having an external surface and a cavity formed in the external surface, the cavity being surrounded by a region of the external surface having a curvature;
• a microelectrode inserted into the cavity, the microelectrode configured to detect electropotentials generated by the body cavity, the microelectrode having a distal surface, and being configured to fit into the cavity so that the outer surface of the microelectrode is contoured, located and oriented to conform with the curvature of the region such that all points on the external surface of the distal tip electrode and the distal surface of the microelectrode located at the same radial distance from the longitudinal axis have a same principal curvature, but all points on the external surface of the distal tip electrode and the distal surface of the microelectrode located at a different radial distance from the longitudinal axis have a different principal curvature;
• and
• two conductors of two different materials connected at a junction to form a thermocouple, and wherein the junction is connected to the microelectrode at a single microelectrode receptacle so as to provide a signal representative of a temperature of the microelectrode to the temperature module through the two conductors, and wherein the processor and at least one of the two conductors is configured to allow electropotentials generated by the body cavity at the microelectrode and the signal generated by the thermocouple representative of the temperature of the microelectrode to be measured simultaneously by the processor.